AP Physics C: Electricity and Magnetism / Unit 10: Conductors and Capacitors
10.2 Redistribution of Charge Between Conductors
Notes
Connected conductors reach the same potential. For spheres: $\displaystyle \frac{kq_1}{r_1}=\frac{kq_2}{r_2}$, so the larger sphere gets more charge.
Practice
Two connected spheres of radii 1 cm and 3 cm share 8 μC. The large sphere has:
Charge proportional to radius.
After connecting, the two spheres have equal:
Same conductor.
The smaller sphere has a larger:
$\displaystyle \sigma\propto\frac{1}{r}$.
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